Engine block cores and engine cylinder head core designs generally include “prints” or protrusions extending outwardly or externally from the side and/or end of the cores. The prints may be used to stabilize the cores and enable clean-out of cores, such as coolant and lubrication cores. However, these prints generally extend through the side and/or end walls of the engine block formed and the resulting openings produced in the external surfaces of the casted engine block reduces the structural rigidity of the block. Additionally, the external openings created by the penetrations extending the wall of the engine block generally require machining and plugging during engine manufacturing, thereby adding cost and time to the manufacturing process.